1. Field of the Invention
The present invention relates to a vehicular lamp, a cold cathode fluorescent lamp lighting apparatus, and a cold cathode fluorescent lamp lighting method.
2. Description of Related Art
Conventionally, a cold cathode fluorescent lamp having a cathode, a gate, and an anode previously applies an acceleration voltage between the anode and the cathode and applies an extraction voltage between the gate and the cathode to discharge electrons from the cathode toward the anode, and then collides the discharged electrons against a phosphor on the anode to cause the phosphor to emit light is known as disclosed, for example, in Japanese Patent Laid-Open No. 2000-173445. In the cold cathode fluorescent lamp, it is required that the extraction voltage when the electrons begin to be initially discharged be applied between the gate and the cathode more highly than that when the electrons are discharged stably.
However, if drop in the voltage is not performed till the extraction voltage to be applied during discharging the electrons stably after the discharge of the electrons starts, superfluous electrons are discharged from the cathode to the anode. Therefore, the anode is overheated, and thus the anode, the phosphor, a glass substrate on which the anode is formed, and so on have been damaged by heat in some cases. To solve this problem, after the discharge of the electrons starts from the cathode by applying the high extraction voltage between the gate and the cathode, it is required that the extraction voltage be rapidly dropt. Thereby, an apparatus for adequately illuminating the cold cathode fluorescent lamp became complicated in some cases. Therefore, there has been a problem that adequate lighting of the cold cathode fluorescent lamp needs high cost.